The sound files of Édouard-Léon Scott de Martinville's phonautograms released during 2008 by the First Sounds collaborative were created using the Lawrence Berkeley National Laboratory's virtual stylus technology, which sought to track the wavy lines scratched on soot-covered paper as though they were standard record grooves. However, Scott did not intend his phonautograms to be played back, and from a modern perspective his tracings are often malformed: the recording stylus sometimes left the paper and sometimes moved backwards along the time axis, violating basic assumptions of the “virtual stylus” approach and—for that matter—of sound recording in general. For this reason, we supposed at first that many of Scott ’s phonautograms—particularly the earliest ones—might remain permanently mute.
In late 2008, First Sounds cofounder Patrick Feaster devised an alternate playback approach, graphically converting phonautographic wavy lines into bands of variable width and playing these back using software designed to handle optical film sound track formats. This approach can’t correct serious malformations in Scott’s phonautograms any more than the “virtual stylus” approach can, but it is sufficiently robust to let us hear something from phonautograms that are otherwise too compromised to process. The phonautographic sound files unveiled by First Sounds since mid-2009 have been produced by Feaster using this approach. For convenience, we will identify the two techniques as VS (“virtual stylus”) and VW (“variable width”).
During 1860, Scott furnished his phonautograms with 250 Hz tuning-fork calibration traces that allow us to compensate for the irregular recording speed of the hand-cranked cylinder. Many phonautograms from 1857 also survive, but they lack the tuning-fork timecode, so in these cases we have no objective means of correcting for speed fluctuations, which are generally great enough to render sung melodies utterly unrecognizable.